CVE-2026-7423

MEDIUM

Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP

Title source: cna
STIX 2.1

Description

Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB. To mitigate this issue, users should upgrade to the fixed version when available.

Scores

CVSS v3 5.3
EPSS 0.0001
EPSS Percentile 3.4%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-191
Status published
Products (4)
AWS/FreeRTOS-Plus-TCP 4.0.0 - 4.2.6
AWS/FreeRTOS-Plus-TCP 4.2.6
AWS/FreeRTOS-Plus-TCP 4.3.0 - 4.4.1
AWS/FreeRTOS-Plus-TCP 4.4.1
Published Apr 29, 2026
Tracked Since Apr 30, 2026